TWI274177B - Film layer structure of spectroscope - Google Patents

Abstract

The present invention relates to a film layer structure of spectroscope, the film layer stacked by materials of high index of refraction and low index of refraction. The film layer structure is (HL)<n>HLH(LH)<n>, where H represents a film layer made by material of high index of refraction, the index of refraction for which is between 2.5 and 4; L represents a film layer made by material of low index of refraction, the index of refraction for which is between 1.4 and 1.7; and n is an integer. After the film layer structure undergoes an optimal operation, a beam splitter with 90 degree phase differences and low separation in P-polarizing light reflectivity and S-polarizing light reflectivity can be obtained. After the film layer structure is optimized, the refractive indices of high index of refraction film layer and low index of refraction film layer are 3.86 and 1.45, respectively, and the value of n is 4.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film layer structure of a spectroscope, a spectroscope and an optical lens, and more particularly to a film structure of a non-polarization spectroscope. [Prior Art] According to the 'Beam Splitter', which is used to reflect or transmit light, the spectroscope can be divided into a neutral spectroscope and a two-color spectroscope according to the spectral characteristics. The neutral spectroscope can split a beam of light into a beam splitter. Two beams of the same spectral composition; a two-color beam splitter reflects one part of the spectrum and transmits the other part. Depending on the polarization of the light, the beam splitter can also be designed as a polarizing beam splitter that splits the beam into s-polarized light whose electric field is perpendicular to the plane of incidence, and p-polarized light whose electric field is parallel to the plane of incidence. The main impurity of the ideal neutral spectroscope is that the reflectivity and the transmissivity of the @ wavelength and the opacity are small and the polarization is small, but the material of the multilayer film always has the properties of dispersion and absorption, and If the incident angle is not zero, then the reflectance and transmittance of light of different polarizations will be different. When the incident angle is larger, Rs (S-polarized reflectance) is familiar (P-polarized reflectance), Ts (S The difference in transmittance of polarized light)#Tp (p-polarized light) is larger, so the optical film layer needs to be specially designed so that the beam splitter becomes a non-polarized beam splitter. The film design of the conventional beam splitter adopts an alternating periodic structure and is formed by stacking high and low refractive index materials. As shown in the first figure, the structure of the film layer 8 is (10) m, which is directly disposed on the substrate Ns. Where '1' represents a high refractive index film layer, L denotes a low refractive index film layer, m is an integer, # when λ° represents the center wavelength of human light, both high refractive index and low refractive index film layer L are set To have an optical thickness that is transferred to μ (the thickness is equal to the refractive index multiplied by 1,274,177 in thickness). However, the phase difference between the s-polarized light of the family layer 8 and the reflected wave of the p-polarized light can only be limited to the G degree. The ft is 90 degrees, which is _ thorn, and (4) the separation of s-polarized light and p-polarized light. The amount is too large, such as the characteristic curve of the green_reflectivity_phase distribution of the second riding. It can be seen that it is necessary to improve the conventional film structure to improve the non-polarization characteristics of the beam splitter. SUMMARY OF THE INVENTION The object of the present invention is to provide a film structure of a spectroscope, which can make the design and acceptance of the spectroscope in a wide range, and the separation of S-polarized light and p-polarized light can also be very high. small. According to the above purpose of the present month, the present invention provides a film layer of the spectroscope, which is formed by stacking the same and low refractive index materials, and the film structure is (5) chat (yang, where H represents a Lay made of a high refractive index material having a refractive index of between 2 and 5 to 4; L means a layer made of a low refractive special material having a refractive branch between 丨.4 and 丨·?; After optimizing the film structure for an integer, a beam splitter with a phase difference of 9 且 degrees and a small separation of the reflectance of the p-polarized light and the reflectance of the S-polarized light can be obtained, and the data of the film layer structure is: high refractive complement The layer has a scale of 3.86, a refractive index of low refractive index, and η is equal to 4 〇. The above-mentioned layer H made of a high refractive index material and the film layer 1 made of a low refractive index material each have an optical thickness approximately equal to Where λ represents the center wavelength of the human light. After the optimization of the film structure, the total thickness of the high refractive index film layer is less than 1274177 80 nm, and the total thickness of the low refractive index film layer L is less than 15 〇〇. The refractive index film layer is made of an absorbent material. Compared with the prior art of the present invention, The film structure of the present invention is (4) (4) (LH)n, the refractive index of the high refractive index film layer is 3.86, and the refractive index of the low refractive index film layer is 1.45 η is equal to 4 '. The phase difference can be obtained by the film layer design. 9 minutes and (p-polarized reflectance) and &amp; (S-polarized reversal) small separation wire, that is, the spectroscope of the present invention overcomes the S-score: 3⁄4 mirror layer structure to reflected wave The disadvantage of large phase design limitation is that the performance of the product is improved. [Embodiment] The spectroscope of the present invention is applied to optoelectronic products such as DVD and CD, and the film layer design can make the spectroscope design on her and more. It is wide and does not change significantly due to temperature fluctuations, thereby improving the performance of photovoltaic products. As shown in the third figure, the film layer of the spectroscope of the present invention adopts a symmetric film system, and the film structure is (HL). nHLH (LH)n, which is directly disposed on the substrate, the film layer has a symmetrical central layer HLH, and the frame represents a thief layer made of a high refractive index material, and its refractive index is at 2·5~ Between 4 and the material is an absorbent material; L represents a film made of a low refractive index material , the refractive index is between 1. 4 and 1. 7; η is an integer, when used; u represents the center wavelength of the human light, the high refractive index film layer Η and the low refractive index film layer L are both set to have An optical thickness equal to λ()/4 (optical thickness is equal to the refractive index multiplied by the thickness). Now the phase difference between the reflected wave of the S-polarized light and the P-polarized light can reach g〇 as an example to design the film structure of the present invention. Make a detailed description. 1274177 According to the phase difference △ = 0 s- 0 p tan —:

Ns sin2 θ0 1 +tan —tan— cosι90sin2 θ0 -2 2 The following formula is obtained: Δ = 2tan' A sin2 θ0 cos ^Ns sin2 (1) The above 0s represents the phase change of the reflected wave of S-polarized light, and 0p represents the p-polarized light. The phase of the reflected wave changes, and Ns represents the refractive index of the substrate, 0. Indicates the angle of incidence of the light. Let Δ = ;τ/2,0f45. Substituting the formula (丨) can be obtained, and when Ns=1512 _ Νι=γ=:|, it is substituted into the following formulas (2) to (5) coefficient P, transmittance T, and reflectance R. Λ ηΟΒ — C Ρ =-- ηΟΒ + C (2) Γ a 27〇ηΟΒ + C (3) ρ a C ;7〇5 — Ci “/7〇5 — C 1 [ηΟΒ + C^ ^ηΟΒ + C ^ (4) T_ 4^0Re(Ky) _ + C)(t/〇5 + C) (5) However, since there is no material with a refractive index of 1.0693, it is necessary to rely on the number when designing the structure of the film. The layer height and low refractive specific materials are matched to obtain the same transmission coefficient r 1274177 reflection coefficient P, transmittance T and reflectance R. In the design process of the multilayer film, the following film matrix will be used: (6) E (zO) H(zO)

M where Μ=Π场· = χ [ cos々7now. M z^sin^ cos&lt;^ 2^r ^ = -Njdjcos^ ;

B

c]=ni cos&lt;^' ή^'][ι ] 7=1 irjsinSj cos The above Mi represents the characteristic matrix of the j-th film, and the heart, the meaning and the mountain respectively represent the phase thickness and refractive index of the film. And film thickness.

The numerical values calculated by the above formula are theoretical values. In practical applications, due to the influence of the composition ratio of materials, the theoretical dynamism is difficult to be directly used, and it is necessary to optimize the number of layers and the thickness thereof according to the theoretical value. It is possible to obtain a beam splitter with a phase difference of 9 且 and a small amount of Rp (p-polarized reflectance) and Rs (s-polarized reflectance), as shown in the fourth figure, and a conventional curve shown in the second figure. _ peak, the amount of separation of _ Rs shown in the fourth ® towel can be _ minimum. In this embodiment, the refractive index of the high refractive index material (the total thickness of the high refractive index film layer is less than 8 〇 nm; the refractive index of the low refractive index material (team) is 1.45, the low refractive index film The total thickness of the layer is less than 15 〇〇 nm: the integer ^ is equal to *, that is, the refractive index film layer has ten layers, and the low refractive index film layer has nine layers. In summary, the present invention has indeed met the requirements of the invention patent. 。 Patent application is filed according to law. However, the equivalent modifications or changes made by those who are familiar with the technology of the present invention in accordance with the spirit of the present invention are covered by the appended patent application. BRIEF DESCRIPTION OF THE DRAWINGS The first figure is a (HL)m beam splitter. The second figure is a characteristic curve of the wavelength (reflection_phase distribution) of (HL)m. The figure is the film structure of the spectroscope of the present invention. The fourth figure is the characteristic curve of the wavelength (reflection-phase distribution) of (HL)n HLH (LH)n in the film structure of the present invention. 1,8 substrate Ns high refractive index film layer Η low refractive index film layer L S polarized light reflectance Rs S polarized light reflected phase Phase Rs P polarized light reflectance RP P polarized light reflected phase Phase Rp P polarized light and S polarized light reflected phase difference Phase RP-Rs

Claims (1)

1274177 Pickup, patent application scope: 1. - Spectroscope _ layer structure, the film layer is composed of high and low refractive index materials, and the film structure is (HLmH(LH)n, where H represents high refraction a film made of a material having a refractive index 疋 between 2.5 and 4; L represents a dielectric layer made of a low refractive index material having a refractive index between L4 and L7; the core is an integer, the film is After the layer structure is optimized, a beam splitter with a phase difference of 9 且 and a small separation of the reflectance of the p-polarized light and the reflectance of the s-polarized light can be obtained. The data optimized for the film structure is: a high refractive index film layer. The folding scale is the top, and the folding scale of the low riding surface layer L is μ, which is equal to 4. 2. For example, the 阙 structure of the spectroscope of the patent model @Di 丨斯, in which the high refractive index layer Η and the low refractive index The film layers L each have an optical thickness of approximately λ 〇 /4, wherein 〇 represents the center wavelength of the incident light. 3. The film structure of the beam splitter according to claim 1, wherein the film thickness is After optimization, the total thickness of the high riding rate is less than 8Gnm, and the total thickness of the low refractive index film L is less than i5. 4. The film structure of the spectroscope according to claim 1, wherein the high refractive index film layer is made of an absorptive material. 5. A spectroscope having a substrate; The symmetrical film layer on the substrate can make the design and application of the beam splitter in a wider phase. The film structure is (HL)n (LH)n, where Η denotes a film layer made of a high refractive index material. The refractive index is between 11 1274177 2.5~4, and the total thickness of the high-refraction (four) layer in the Lang layer is less than 8〇 lung; the L-plane is supported by a low-refraction special, and the fold is between u~17 The total thickness of the low refractive index dielectric layer in the film structure is less than 1500 nm; and η is an integer. 6·If the application __ 5 item riding spectroscope, wherein the refractive index of the high folding scale riding material is 3· 86. The refractive index of the material of the low refractive index film layer is 1.45, and η is equal to 4. The beam splitter according to the sixth aspect of the patent application, wherein the high refractive layer is made of an absorptive material. An optical lens having a symmetric film system, the film system is disposed on a substrate, and the film has a pair of structures HLH The central layer, wherein Η denotes a film layer made of a high refractive index material, the refractive index of which is between 2. 5 and 4; L represents a film layer made of a low refractive index material, the refractive index of which is 1 And an optical lens according to the eighth aspect of the invention, wherein the optical lens according to the eighth aspect of the invention, wherein The enamel layer is an absorbing material. The optical lens according to claim 9, wherein the enamel layer has a refractive index of 3.86. The optical lens, wherein the [layer has a refractive index of 1.45. 12. The optical lens of claim 11, wherein the structure is (LH)n 12 (S> 1274177 The η in the extension layer is equal to 4. The optical lens of claim 8 or claim 12, wherein the Η and L film layers each have an optical thickness of about 1 〇 / 4, wherein 1 〇 is the center wavelength of the incident light 0 13 1274177 柒, designated representative map: (1) The representative representative of the case is: (3). (2) The symbol of the representative figure of this representative figure is briefly described: film layer 1 substrate Ns high refractive index film layer Η low refractive index film layer L 捌 If there is a chemical formula in this case, please reveal the chemical formula that best shows the characteristics of the invention: